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<title>Removing Species with a "*"</title>
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<p><b>Removing species:</b> If the first character in the name for a chemical species
is an asterisk <nobr>(*),</nobr> the species will not be included in the calculations.
This is a quick method to <u>deactivate</u> a species without having to remove it from the
input data file.</p>

<p>It is convenient to
<a href="S_Modify_Chem_System.htm#deactivate">deactivate species using SPANA</a>.</p>

<p>Note that if you <u>deactivate a component</u> in this way, then only the
<i>free</i> component is removed from the mass balance.
For example, if the components are <nobr>H<sup>+</sup></nobr> and
<nobr>AlOOH(cr)</nobr> and you deactivate the Al oxyhydroxide by
changing its name to <nobr>*AlOOH(cr)</nobr>, then you suppress the
precipitation of that solid in the calculations, but aluminium is <u>not</u>
removed: the Al-complexes <nobr>AlOH<sup>2+</sup>,</nobr>
<nobr>Al(OH)<sub>3</sub>(cr),</nobr> etc, still remain.
<a href="S_Diagr_FractAl.htm">Example</a>.</p>

<p>Note that some species <nobr>(H<sub>2</sub>O,</nobr> <nobr>e<sup>&#8722;</sup></nobr>
and <a href="ChEq_Gases.htm">gases</a>) always have
<a href="SP_Species_Zero_Conc.htm">zero concentration</a> and therefore,
for them it is <b>not necessary</b> to add a &#147;*&#148; as the
first character.</p>
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